Synonyms for Yowl (same or very similar meaning)
WordNet sense 1 (a very loud utterance (like the sound of an animal)):
bellow, holler, roar, roaring, bellowing, holla, hollering, hollo, holloaWordNet sense 2 (cry loudly, as of animals):
howl, yammer, wrawlWordNet sense 3 (utter shrieks, as of cats):
caterwaulFrom the ODE community, based on WordNetadd/edit